Much emphasis has been placed on the mileage performance of passenger vehicles in recent times. In particular, air drag represents a major component of gas expenditure during a normal vehicle driving process. As a result, aerodynamic enhancements to the design of cars and other motor vehicles have been a significant focus in recent decades. Efforts to improve the aerodynamic features of vehicles include developments to spoilers, vehicle shape, vehicle size, and materials.
While such technology has been advantageously applied to small commercial vehicles, large vehicles such as tractor-trailer rigs are a far bigger user of fuel on a proportional basis. While some of the same technological advantages that are used on cars can be used on such trucks, the shape of such trucks is one (1) significant disadvantage of the truck-trailer combination cannot be overlooked. The general box shape of trucks that is so advantageous when hauling goods is terrible when going down the highway. This poor aerodynamic shape coupled with the high weight of a tractor-trailer rig results not only in poor fuel economy, but places increased stress and strain upon the engine, tires, suspension components and the like. This poor fuel economy and high operating costs results in not only reduced profits for the owner, but higher cost for all.
Various attempts have been made to provide air manipulating or deflecting assemblies for large vehicles. Examples of these attempts can be seen by reference to several U.S. Pat. No. 3,596,974, issued in the name of Adams, describes an air current deflecting device for a car or the like while towing a larger, flat-fronted object such as a trailer.
U.S. Pat. No. 4,082,340, issued in the name of Taylor, describes an air current deflecting device with a bellows style angle adjustability feature for reducing drag across a top surface of a vehicle.
U.S. Pat. No. 4,156,543, issued in the name of Taylor et al., describes a similar air current deflecting device with a bellows style angle adjustability feature particularly adapted for use on the cab of a tractor trailer combination.
U.S. Pat. No. 5,513,894, issued in the name of Ragsdale, describes a rigid air deflecting tank particularly adapted for use on the roof of a tow vehicle.
While these devices fulfill their respective, particular objectives, each of these references suffer from one (1) or more of the aforementioned disadvantages. Many such devices are not adapted for use on the trailer portion of a tractor trailer combination. Also, many such devices are not adjustable. Furthermore, many such devices are not easily manipulated from an elevated position, such as the top of a trailer. In addition, many such devices are unmanageable while driving. Accordingly, there exists a need for an air foil for large motor vehicles without the disadvantages as described above. The development of the present invention substantially departs from the conventional solutions and in doing so fulfills this need.